NITROGEN AND PHOSPHORUS 



' Grain Farming vs. Stock Farming in Maintaining Fertility 



347 



* Residue means grain straw, corn stalks, clover straw, chaff, etc. 



Lime. Application of 250 pounds air-slaked lime per acre in 1902; 600 

 pounds pulverized limestone per acre in 1903; beginning with 1911, pulverized 

 limestone is added at the average rate of two tons per acre every four years. 



Manure is applied at the rate of one ton for every ton of produce. 



Phosphate. 200 pounds of bone meal were applied to the acre annually 

 up to 1908, then plot was divided and one-half continued to receive bone meal 

 at the average rate of 200 pounds per acre per year. 



To the other half is applied rock phosphate at the average rate of 600 

 pounds per acre per year. 



These results show clearly that a good grain farmer can main- 

 tain and increase the fertility of the soil. 



Combination of Grain and Stock Farming. The fact that 

 considerable roughage is produced on grain farms has encouraged 

 the keeping of more or less livestock to convert this by-product 

 into useful animal products, and at the same time manure is pro- 

 duced for use as fertilizer. Thus, roughages of one kind or another 

 will, no doubt, give the dairy cow and the beef animal especially, 

 a place in our agriculture for a long time to come. 



AN ACCOUNT WITH THE PLANT-FOOD ELEMENTS IN FARMING 



Nitrogen and Phosphorus Balance Indicative of Good Farming. 



There are several factors which determine the productive 

 power of soils. When all other conditions are favorable, how- 

 ever, the balance of nitrogen and phosphorus in the soil in any 

 rational system of farming will indicate very clearly the tendency 

 towards soil enrichment or soil depletion. For example, the draft 

 per acre on the plant-food elements on a grain farm during a four- 

 year period when the corn is " snapped" 6 and no straw is returned, 

 may be as follows : 



6 When the ears are jerked off the stalks in the field this method of harvest- 

 ing is called "snapping the corn." The stalks are left in the field. 



